The key to reversing the hands of time may start on a chromosomal level. Scientists from the Spanish National Cancer Research Centre (CNIO) have discovered it is possible to trigger telomerase activation and telomere elongation through in vivo tissue reprogramming, reversing the signs of aging.

The paper, published in Stem Cell Reports, describes how the lengthening of telomeres is an unmistakable sign of cell rejuvenation. CNIO scientists regressed cells in “reprogrammable mice” to an embryonic-like state by administering an antibiotic to turn on the expression of the four Yamanaka factors (OSKM).

Scientists also noted lengthening telomeres during in vivo reprogramming, leading to dedifferentiation of tissues. This elongation marks the cellular rejuvenation taking place due to the action of telomerase, and the first occurrence recognized in a living organism.

“We have found that when you induce cell dedifferentiation in an adult organism, the telomeres become longer, which is consistent with cellular rejuvenation,” said María A. Blasco, head of CNIO Telomeres and Telomerase Group and leading author.